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Safety relay module SRM 21 RT2
Technical data
Standards | EN ISO 13849-1,-2; EN 62061; EN 60204-1, EN ISO 13850; EN 60947-5-1; GS-ET 20 |
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Enclosure | black polycarbonate; polyamide terminal clamps V0 |
Contact material | AgNi 10 + 0.2 µm Au |
Mounting | DIN rail mounting |
Connection | screw terminals with + and - screws |
Cable cross-section | min. 1x 0.5 mm² (AWG 20) including conductor ferrules, max. 1x 2.5 mm² (AWG 14) including conductor ferrules, 2x 1.5 mm² (AWG 16) including conductor ferrules |
Degree of protection | Enclosure IP 40, Terminal block IP 20 to IEC/EN 60529, shock protection to VBG 4 |
Safety-relevant data:* | |
EN 60204-1 | stop category 0 |
EN 62061 | SIL CL 3 |
PFHd | 3 x 10-8 1/h |
EN ISO 13849-1 | PL e, Category 4 |
MTTFd | > 113 years |
TM | max. 20 years |
DC/DCavg | > 99 % |
Safety requirements nop | |
hop | 8 h/day |
dop | 220 days/year |
tzyklus | 30 s |
Rated operating voltage Ue | 24 VDC ±15 % |
Rated operating current Ie | 0.125 A |
Rated operating isolation voltage Ui | 250 VAC |
Rated impulse withstand voltage Uimp | 4 kV |
Conditional short-circuit current | 100 A |
Inputs | 1 NC/1 NO contact or 2 NC contacts, 1 feedback circuit, 1 start input (monitored) |
Outputs | 2 enabling paths, 1 transistor output as signalling output |
Ie/Ue enabling paths | 2 A/230 VAC; 1 A/24 VDC |
Utilisation category | AC-15; DC-13 |
Contact load capacity | min. 10 mA |
Typ. input current/ voltage | 22 mA/ 20 VDC |
Max. load of signalling output | 20 mA |
Max. fuse rating | power supply 2A slow blow, enabling paths 6 A gG/gN fuse |
Delay on energisation/ deenergisation | ≤ 20 ms |
Risk time | ≤ 0.5 s (switch-on delay) |
Attendance delay tv | < 200 ms |
Mechanical life | > 50 million operations |
Display | 1 LED for supply voltage, 1 LED each for input A and B, 1 LED for authorisation |
Degree of pollution | 2 to DIN VDE 0110 |
Overvoltage category | III |
Ambient temperature | –22 °C … +55 °C |
Storage and shipping temperature | –22 °C … +70 °C |
Relative humidity | 10 % ... 90 % |
Shock resistance | 3 g |
Approvals | ![]() ![]() |
Note | Inductive loads (contactors, relays etc.) are to be suppressed by suitable circuitry. |
Weight | 220 g |
Ordering details |
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Type | Material no. | |
Safety relay module SRM 21 RT2 | 1179203 |